River information management and flood forecasting in Japan

Transcription

1 River information management and flood forecasting in Japan Tomonobu SUGIURA Senior Researcher Hydrologic Engineering Research Team Management (ICHARM)

2 Contents 1. Objectives of river information management 2. Collection, processing and provision of real-time data 3. Provision of disaster information 4. Predicted rainfall 5. Run-off analysis and flood forecasting 6. Utilization of satellite-based rainfall information

3 1. Objectives of river information management

4 1-11 Objectives of river information management Accurate, reliable and quick collection, processing and dissemination of river information (e.g. rainfall amounts and water levels in rivers) River information Water levels Rainfall amounts Images Water quality Collection Refinement of planar data Refinement of image data Processing Centralization of data Refinement of prediction data Regional FM radio station Provision Refinement of contents Improvement of information dissemination tools Regional FM radio station User Increasing the efficiency of river-related work Newspapers Media Radio station Local municipality/public institution Enhancing river administration services through information dissemination to the public The Internet Broadcasting station/catv

5 1-22 Adaptation measures to decreasing loss of life Since it is difficult to totally protect everything from flood and other disasters, which are likely to be intensified by climate change, adaptation strategies for climate change need to be developed aiming for zero victims. Enhancing river information management is one of adaptive measures to decreasing loss of life. Proposal of specific adaptation strategies Climate Change Adaptation Strategies to Cope with Water-related related Disasters due to Global Warming (Draft Policy Report) (1)Adaptation strategies using structures (2)Adaptation strategies in step with local community development (3)Adaptation strategies with emphasis on crisis management 1)Promotion of preparation for responding to large-scale disasters 2)Promoting non-structural measures based on new scenarios 3)Enhancement of forecasting and warning systems for floods, sedimentdisasters and flood fighting To conduct such activities as flood fighting, evacuation and emergency restoration in disaster management, it is very important to provide residents and relevant organizations with forecasts and warnings based on the prediction of the precursors, timings and scales of floods, debris flows and storm surges. (4)Adaptation strategies to avoid drought risk (5)Adaptation strategies to river environment changes (6)Enhancement of observational systems for the impacts of climate change

6 2. Collection, processing and provision of real-time data

7 2-11 Collection of real-time data Collection of point data (e.g. rainfall amounts, water levels and water quality) Rain observation by ground gauges Telemetry system Collection of area data (rainfall amounts) Radar rain gauge Collection of image data CCTV network Fiber optic network

8 Rain observation by ground gauges Tipping-Bucket Rain Gauge Rain gauge Observation sites Diagram of Telemeter Data Collection in Prefecture A The data obtained by telemeters are consolidated in one site, such as a regional bureau and a prefectural office, through the linking station. Then, they are sent to each office to update the real-time flood prediction calculations.

9 Telemetry system Rainfall amount Mean rainfall amount in the basin Snow cover Water level Water intake Water quality Dam Weir Pump station Weather Oceanographic conditions Groundwater level Total Maritime Safety Geographical Japan Water Other River Bureau Municipality Road Bureau Meteorological Total Agency Survey Institute Agency Agency organization Number of telemetry stations *1 Japan *1 Stations using a uniform river information system (as of March 2007)

10 Locations of radar rain gauges Radar rain gauges have been installed at 26 locations throughout the country. The information of 1-km mesh resolution is updated every half an hour and available on the Internet. The radar data are calibrated using the ground data.

11 CCTV network Ministry of Land, Infrastructure and Transport, Regional Development Bureaus and River Offices have real-time access to 3,900 CCTV images available on IP (Internet protocol) network. Hokkaido Number of CCTV sets installed Road 1,095 Estimate at the end of March, 2007 River 725 Sediment control 55 Other 17 Total 1,892 CCTV images are used for developing disaster control plans. Tohoku Kanto Hokuriku 841 1, , ,551 2,512 1,259 Chubu ,789 Kinki ,564 Chugoku ,495 Shikoku ,026 Kyushu 742 1, ,948 Sample image (Yodo River in Osaka on August 14, 2007) Okinawa Total 50 7, , Source: Data collected by Electricity and Telecommunication Office in October ,132

12 Fiber optics network Total:12,046Km(2006) Hokkaido Development Bureau Kyushu Regional Development Bureau Okinawa General Bureau Chugoku Regional Development Bureau Shikoku Regional Development Bureau Lines constructed Hokuriku Regional Development Bureau Kinki Regional Development Bureau National highways (under direct jurisdiction of MLIT) River sections under direct jurisdiction of MLIT Constructed at the end of fiscal 2005 To be constructed by the end of fiscal 2006 To be constructed by the end of fiscal 2007 Chubu Regional Development Bureau Kyushu National Institute for Land and Infrastructure Management Kanto Regional Development Bureau Ministry of Land, Infrastructure and Transport (MLIT) Chugoku Shikoku Kinki Tohoku Regional Development Bureau Hokuriku Chubu Kanto Ministry of Land, Infrastructure and Transport Okinawa Tohoku National Institute for Land and Infrastructure Management Hokkaido WDM (east loop, 4.8 Gbps) WDM (west loop, 4.8 Gbps) Ethernet (1 Gbps) Telecommunications carrier's lines, etc. River Bureau and Road Bureau have jointly laid fiber optics network lines.

13 2-22 Uniform river information system Foundation of river and basin integrated communications (FRICS) developed an integrated river information system. The uniform river information system aims at sharing and standardizing river administration data including river water levels and rainfall amounts. River information systems developed by individual regional development bureaus have been integrated into a national river information system. Regional development bureaus can customize the system according to their requirements.

14 River disaster prevention information Information to be provided Radar rain gauge data Telemetry data (water levels, rainfall amounts, etc.) Flood forecasting and warning Dam-related parameters (notice of release of water from the reservoir, reservoir water storage, etc.) Water level graph Portal of "river disaster prevention information" website Hyetograph

15 Data provision via the Internet and cellular phone River disaster prevention data such as water levels, rainfall amounts and damrelated parameters have been disseminated since fiscal 2001 via the Internet and cellular phone. Numerous improvements have been made since fiscal 2007 such as additional provision of data of prefectural governments and applicability to all cellular phone service companies. The Internet since April Cellular phone (since April 2001) *Applicable to multiple carriers including au and Softbank since April 2007.

16 3. Provision of disaster information

17 3-1 Hazard map prepared by a municipality Hazard map in Kurihashi town Image of a hazard map 1)General Information Flood Risk Areas, Types of damage Ways to provide evacuation information (flood forecasts, etc.) Sources of weather information, etc. Evacuation sites, Dangerous areas during evacuation 2)Area-Specific Information (Information for Evacuation) Flood information in other areas than flood risk areas Flood characteristics of rivers, Issues on evacuation orders Evacuation zone, Tips for evacuation Information on the facilities for people who are particularly vulnerable to disasters Information on underground malls

18 3-22 Water-level display tower, etc. The water-level display tower to indicate the current WL of River B with red lights. Altitude (m) Tokyo and the Edo, Ara, Sumida Rivers Keihin Tohoku Railroad Line Sumida River Ara River Ayase River Naka River Ohba River Edo River Saka River Shin Saka River Joban Railroad Line Musashino Railroad Line National Route 6 Flood water depth (projected) Sign in town Kita Ward Arakawa Ward Adachi Ward Katsushika Ward Misato City Matsudo City

19 3-33 Awareness program To enhance a flood awareness of residents River information (under normal condition) Residents understand a flood risk, and how to act and where to evacuate in flood. River information (under abnormal condition) Residents can make an accurate judgment to start evacuation.

20 4. Predicted rainfall

21 4-11 Short-period rain prediction Short-Period Rain Prediction is issued every 30 minutes to provide forecasts of one-hour precipitation for the next 6 hours with 1-km spatial resolution. Not only changes in rain distribution, but also geographical factors and numeric estimates are taken into considerations. 1 hour 2 hours 3 hours 4 hours 5 hours 6 hours

22 4-22 Precipitation nowcast Precipitation Nowcast provides 10-minute precipitation forecasts with 1-km spatial resolution up to one hour ahead. Since it gives priority to quick forecasting, the precision is not as high as the Short-Period Rain Prediction. However, it is very useful for swift disaster-prevention activities. 10 minutes 20 minutes 30 minutes 40 minutes 50 minutes 60 minutes

23 5. Run-off analysis and flood forecasting

24 Flood prediction by storage function model Most commonly used in Japan. It predicts a runoff volume of the prediction site by a runoff model using the storage function method and a water level by means of the H-Q equation.

25 Flood prediction by distributed model It is a physical model which segments a basin into meshes and calculates a runoff volume assuming that rain falls on each mesh. With this method, rain distribution is modeled more precisely in comparison with the Storage Function Model. Rainfall Surface flow of water Modeling Flow of water in the ground Flow in the river channel Q converted to H by the H-Q equation

26 Flood forecasts jointly announced by MLIT and JMA Japan meteorological Agency Rainfall JMA Forecast Department District Meteorological Observatory Local Meteorological Observatory Weather information MLIT Regional Bureaus River Offices River Information Ministry of Land, Infrastructure, Transport and Tourism Water Level Joint Announcement Types of flood forecasting 1.Flood Alert Information 2. Flood Risk Information 3. Flood Information (Flood-Fighting information (MLIT)) Press and Broadcast Agencies Local Residents Government Flood-Fighting Organizations

27 5-2-2 Water levels used to issue flood forecasts Example of Flood Forecasts Levee Centre for Water Hazard Hazard and Risk

28 Flood forecasts Flood Forecasts by JMA Announced by the local meteorological observatory of JMA in its area of administration. Medium- to small-size rivers other than those designated for flood forecasts Weather advisories Weather warnings Flood advisories Flood warnings Announced when disasters may occur by heavy rain, gale, high tide, etc. Announced to warn of a risk of serious disasters by heavy rain, gale, high tide, etc. Announced when floods may cause damages Announced to warn of a risk of floods Warnings for Flood Fighting issued by MLIT Issued with the purpose for MLIT or the prefectural government to provide flood-fighting organizations with a guideline for their activities. Standby Preparation Mobilization Alerts that flood-fighting fighting organizations need to be ready for operation in case floods may occur or WL is predicted to increase. Warns that flood-fighting fighting organizations need to be prepared for operation, at the same time, sending information about flood control, providing flood control equipments and materials, securing communication and transportation means. Warns that flood-fighting fighting organizations need to be mobilized when WL is predicted to exceed the Flood Alert WL.

29 6. Utilization of satellite-based rainfall information Adaptation measurement in developing country

30 6-11 Necessity of satellite-based rainfall data In the countries where river improvements are not sufficient, smooth evacuation from flooding is important for decreasing loss of life and properties. Dissemination of risk by hazard maps, etc. and direction of evacuation by issuing flood forecasts and alerts are necessary. However, in reality, development of a flood warning system in these countries has not advanced properly because of financial difficulty, lack of rainfall data, etc. Non real time observation Technical issues for flood forecasting No data of river discharge

31 Features of satellite-based rainfall data (3B42RT) Current System Launch of Tropical Rainfall Measuring Mission (TRMM) satellite in 1997 Near real time data 3B42RT since 2002 from TRMM, orbital satellites and geostationary satellites Features 3-dimensional analysis of rainfall structure Global coverage including oceans 3B42RT:NASA Mesh Size: 0.25 degrees of latitude and longitude (rectangle of about 30km by 20km on 40N) Coverage Area: between 60N and 60S latitude Data Delivery: every 3 hours (not hourly) Near-real real-time basis with several hours time lag ftp://trmmopen.gsfc.nasa.gov/pub/merged/mergeirmicro trmmopen.gsfc.nasa.gov/pub/merged/mergeirmicro/ 3B42RT Product name 3B42RT CMORPH QMORPH Builder NASA/GSFC NOAA/CPC NOAA/CPC Coverage 60N60S 60N60S 60N60S Spatial resolution km km 0.25 Time resolution 3hours 30minutes 3hours 1day 3hours 30minutes 30minutes Delay of delivery 10hours 15hours 2.5hours Timing of data updating Every 3hours Every 30minutes Every 3hours Every 1day Every 3hours Every 30minutes Every 30minutes UTC UTC UTC UTC UTC UTC UTC Coordinate system WGS Data archive Dec Recent 4days Dec Jan Dec Recent 2days Data source TRMM-TMI DMSP-SSM/I Aqua-AMSR- E,AMSU-B IR Product of satellite-based rainfall data TRMM-TMI DMSP-SSM/I Aqua-AMSU-B IR Satellite-based rainfall in Tone river in Japan

32 Accuracy of satellite-based rainfall data 50 Upstream area of sameura dam, area=472km2 Satellite-based rainfall data(mm/h) Upstream area of ikeda dam, area=1,904km2 R 2 = R 2 = Ground-based rainfall data(mm/h) Comparison with satellite-based and ground-based rainfall (major ten flood in ) Comparison with satellite-based and ground-based rainfall of Sameura dam basin

33 6-33 Flood forecasting system for developing country Our team is developing a concise flood-runoff analysis software as a toolkit. This system implements interfaces to input not only ground-based but satellitebased rainfall data, GIS functions to construct flood-runoff models, a default runoff analysis model, and interfaces to display output results. Rainfall data Flood forecasting Disaster mitigation NASA HP (Satellite-based rainfall) Integrated Flood Analysis System

34 6-44 Modeling function Intake of digital elevation data Create a basin boundary automatically automatically IFAS creates a basin boundary and a river channel network use of digital elevation data. Create a river channel network Landuse data GLCC (USGS HP) Land Cover Classification (GLCC) IFAS Classification Urban and Built-Up Land Urban area Dryland Cropland and Pasture Irrigated Cropland and Pasture Wetland Mixed Dryland/Irrigated Cropland and Pasture Cropland/Grassland Mosaic Cropland/W oodland M osaic Grassland Grassland Shrubland Mixed Shrubland/Grassland Savanna Deciduous Broadleaf Forest Deciduous Needleleaf Forest Evergreen Broadleaf Forest Forest Evergreen Needleleaf Forest Mixed Forest Water Bodies Water Bodies Herbaceous Wetland Wetland Wooded Wetland Barren or Sparsely Vegetated Herbaceous Tundra W ooded Tundra Grassland Mixed Tundra Bare Ground Tundra Snow or Ice W ater Bodies IFAS estimates parameter based on the classification that we set up beforehand. Set parameter automatically

35 6-55 Example display of our flood forecasting system River channel network Hydrograph Calculation results Parameter estimation Water level of a upper tank River discharge

36 6-66 On going works Improvement accuracy and resolution of results: to calibrate a set up parameter with some large basins to implement functions united at the distribution time delay and updating time of satellite-based rainfall (correcting function of satellite-based rainfall using ground based rainfall) Display an inundation depth: to implement a linkage function with an inundation model Tonle Sap Lake Flood in 2003 We hope this system is useful for immediate and efficient implementation of flood forecasting and warning system in developing countries.